1. Field of the Invention
This invention relates generally to a cooling apparatus for combustion chambers of water-cooled engines, and more particularly to a steam relief device at the upper backward part in the water-jacket.
2. Description of the Prior Art
Referring to the water-cooled engine provided with the radiator in its front part, the cooling water inlet and outlet are formed through the lower front part and the upper part of the water-jacket, respectively, and the inlet and the outlet communicate with the lower tank and the upper tank of the radiator, respectively. Through above flow circuit of the cooling-water, the cooling-water circulates between the water-jacket and the radiator, whereby the combustion chambers are cooled.
However, according to such prior cooling apparatus structure, following vital defects were inevitable and caused many problems. For example, in case of the water-cooled engines mounted on an agricultural machine, it is often necessary to operate the engine in the inclined condition toward front for many hours. And in such a case, the steam generated in the water-jacket remains in the upper backward part of the jacket, and this part is filled with the steam instead of the cooling-water, wherein water cooling cannot be done effectively, and therefore overheated steam causes vapourization of the cooling-water and enlarges the vapour space.
As a result, overheating of the water-jacket around the combustion chamber causes vital damages such as deformations of the cylinder-head and cracks around the suction port or the exhaust port. And sometimes hot water bursts out from the radiator cap attached on the upper tank of the radiator, because of high steam pressure.
The present invention serves to solve the above problems, the characteristics exist in the following.
For preventing gathering of the steam in the upper backward part of the water-jacket, a steam relief device is provided, separately or non-separately with the pressure regulating device for the upper tank of the radiator. According to the present invention, the following effects can be attained. As is provided on the engine, the steam relief device communicates with the upper backward part in the water-jacket. Even when the engine is operated in an inclined position toward front for many hours, the steam with over-pressure never gathers in said upper backward part. Therefore, the steam never fills in the upper backward part of the water-jacket, and the engine can be watercooled effectively. Thus, the above described problems can be solved completely.